<html lang="en">

<head>
  <meta charset="utf-8">
</head>

<body>
  <label>
    <input type="radio" name="radio" value="radio1"> Radio 1</label>
  <label>
    <input type="checkbox" name="checkbox" value="checkbox1"> Checkbox 1</label>
  <select>
    <option value="option1">Option 1</option>
  </select>
  <script type="text/javascript">
    Array.from(document.querySelectorAll('[value=radio1]'))
      .forEach(x => x.checked = true)
    Array.from(document.querySelectorAll('[value=checkbox1]'))
      .forEach(x => x.checked = true)
    document.querySelector('[value=option1]').selected = true;
  </script>
</body>